[Mailman-Users] Mailman Delivery Issue

[Lee Haynes]

When an email is posted to a list or Mailman generates an email, the message
is never delivered, and I receive an error in smtp-failure:

Low level smtp error: (60, 'Operation timed out'), msgid:
<mailman.2.1149803348.35306.all-to at lists.domain.org>

No information is logged by sendmail to maillog.

Outside of Mailman, mail on the server is functioning. I don't believe it to
be a name resolution problem; however, I could be mistaken. I visually
double-checked my hosts file and also made sure the server's name resolves
from the command line.

I also updated mm_cfg.py with a DEFAULT_URL_HOST and DEFAULT_EMAIL_HOST - I
tried using the name and ip for DEFAULT_EMAIL_HOST.

I'm stumped. Any suggestions would be much appreciated.

Thanks in advance.

-Lee